Briggs & Stratton 120000, Instruction Manual

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2
2
4. Turn key switch ON. Meter should display
battery voltage.
If meter does not display battery voltage, the
problem is with the solenoid wiring, equipment
wire harness, or the keyswitch. Repair or replace
as required.
3) Check Compression
Use Leakdown Tester #19545 to check the
sealing capabilities of the compression
components.
Follow the instructions provided with the tester to
perform the leakdown test.
NOTE: Any air leaks at the connections or
fittings of the tester will affect the accuracy of the
test.
Listen for air leaking from the cylinder head
gasket, carburetor, exhaust system, and the
crankcase breather tube.
• Air flowing between the cylinder and
cylinder head indicates that the cylinder
head gasket is leaking.
• Air flowing from the carburetor indicates
air is leaking past the intake valve and
seat.
• Air flowing from the exhaust system
indicates air is leaking past the exhaust
valve and seat.
• Air flowing from the crankcase breather
tube or high oil fill dipstick tube indicates
air is leaking past the piston rings.
Possible Causes for Poor Compression:
• Loose cylinder head bolts
• Blown head gasket
• Burned valves, valve seats and/or loose
valve seats
• Insufficient tappet clearance
• Warped cylinder head
• Warped valve stems
• Worn bore and/or rings
• Broken connecting rod